Can right axis deviation occur on an ECG when the QRS complexes are positive in leads I, II, III, aVL, aVF and negative in aVR?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: February 16, 2026 • View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

ECG Axis Interpretation: Right Axis Deviation with Positive QRS in Leads I-III

No, you cannot have right axis deviation when QRS complexes are positive in leads I, II, and III. The pattern you describe—positive QRS in leads I, II, III, aVL, and aVF with negative QRS in aVR—represents a normal axis (approximately +30° to +90°), not right axis deviation. 1

Understanding the QRS Axis

The QRS axis is determined by the net direction of ventricular depolarization in the frontal plane. Here's how to interpret your specific pattern:

Your Described Pattern Indicates Normal Axis

  • Positive QRS in lead I means the axis is between -90° and +90° 1
  • Positive QRS in lead II means the axis is between -30° and +150° 1
  • Positive QRS in both leads I and II together localizes the axis to the normal range of approximately 0° to +90° 1
  • Positive QRS in aVF confirms the axis is inferior (positive), typically between 0° and +180° 1
  • Positive QRS in aVL with positive lead I further supports a normal leftward axis 1

Definition of Right Axis Deviation

Right axis deviation requires the QRS axis to be ≥+90°, and the American College of Cardiology states this finding is required for diagnosis of right ventricular overload in nearly all cases. 1

The key ECG features of right axis deviation include:

  • Lead I must show a predominantly negative QRS complex (more S wave than R wave) 1
  • Lead aVF remains positive (as the axis shifts rightward beyond +90°) 1
  • Lead II typically remains positive but may become equiphasic as axis approaches +90° 1
  • Lead III becomes strongly positive with tall R waves 1

Common Pitfall: Lead Misplacement

Your described pattern could theoretically result from lead misplacement, which is a critical consideration:

  • Transposition of left and right arm leads produces inversion of lead I with a switch of leads II and III, and aVR and aVL switch positions while aVF remains unaltered 2
  • This creates a false appearance of right axis deviation when the actual axis is normal 2
  • A clue to lead misplacement is important discordance between lead I and V6—normally these leads show similar P-wave and QRS morphology 2
  • The American Heart Association recommends that medical personnel receive training on lead-switch recognition, and ECG machines should incorporate lead-switch detection algorithms 2

Clinical Algorithm for Axis Determination

To accurately determine if right axis deviation is present:

  1. Verify lead placement first—check that lead I morphology matches V6 2
  2. Examine lead I: If predominantly positive (R > S), axis is between -90° and +90° 1
  3. Examine lead aVF: If positive, axis is between 0° and +180° 1
  4. If both lead I and aVF are positive, the axis is normal (0° to +90°)—right axis deviation is excluded 1
  5. For right axis deviation to exist, lead I must be predominantly negative (S > R) while aVF remains positive 1

Age-Specific Considerations

The definition of right axis deviation varies by age:

  • Adults: Right axis deviation is ≥+90°, with moderate RAD at +90° to +120° and marked RAD at +120° to +180° 3
  • Neonates: Normal axis ranges from +30° to +190°, so what appears as right axis deviation in adults may be normal 3
  • Ages 1 month to 1 year: Normal axis is +10° to +120° 3
  • Ages 1 to 5 years: Normal axis is +5° to +100° 3

Never apply adult criteria to pediatric patients, as this leads to false-positive diagnoses of right axis deviation. 3

References

1
Guideline

Electrocardiographic Signs of Right Ventricular Overload

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

2
Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

3
Guideline

V-Paced Rhythm Axis Interpretation

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2026

Related Questions

Does randomization guarantee that both measured and unmeasured confounders are evenly distributed across treatment groups?
How do you convert 2.5% to mg/ml?
What is the diagnosis and management for a patient of unknown age and medical history experiencing intense pulsations in the upper back, abdomen, and occasionally eyelids without associated pain?
What are the differential diagnoses for a ~2.5 mm focally enhancing nodule in the pons on MRI?
Can you analyze a case?
How should I manage a 15‑year‑old adolescent who has intestinal helminths in his stool and a glucose of 56 mg/dL—should I treat the parasites, confirm whether the glucose was obtained after an overnight fast, evaluate for hypoglycemia symptoms, advise on regular meals and balanced snacks, and arrange appropriate follow‑up?
What is the recommended acetazolamide dosing regimen to reduce cerebrospinal fluid production and lower intracranial pressure in an adult patient?
What should be done for a patient who cannot tolerate ondansetron (Zofran) due to side effects such as headache, constipation, diarrhea, dizziness, QT‑interval prolongation, or an allergic reaction?
What are the recommended first‑line and alternative treatment regimens, dosing, and observation criteria for acute otitis media in children and adults, and how should chronic otitis media with effusion be managed?
Is olanzapine (Zyprexa) effective for treating alcohol‑withdrawal hallucinations?
What are the non‑infectious causes of acute febrile illness in adults and what initial work‑up should be performed?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.

Ask Question